Names

Taxonomy and Subspecies

Formerly considered a subspecies of the Eastern Imperial Eagle. Today treated as a seperate
species. Forms a superspecies with the Eastern Imperial Eagle.
The closest relatives of the Spanish and Eastern Imperial Eagle are probably the Steppe Eagle Aquila nipalensis and the
Tawny Eagle Aquila rapax . [GRIN 2009]

Size

Length: 78-82 cm
Wingspan: 180-210 cm
Weight: 2,500-3,500 g

Maximum Age

More than 40 years in captivity. [Mebs & Schmidt 2014]

Habitat

Mostly found in Mediterranean forests but also in marshes like in the Doñana national park.
The Spanish Imperial Eagle can also be found in "Dehesas", a typical wooded pastureland found in Spain. Enough prey, especially
rabbits are important.
Sometimes, the Spanish Imperial Eagle can also be found in agricultureal areas, similar to the
Eastern Imperial Eagle. In Castilla La Mancha, there is a nest in a small group of
poplar trees surrounded by agricultural fields and olive plantations and only a few hundred meters away from a
farm (pers. observation). There are many rabbits in that territory. If left alone, the eagles can live in places like
that and successfully raise young.

Distribution

Restricted to the Iberian Peninsula. Almost the whole world population breeds in Spain. Recently, a few pairs recolonised Portugal.
Was considered extinct in Morocco, but there was a breeding in 1995. Maybe there are still a few pairs left.
Also bred in Algeria in the 19th century, but now extinct. [GRIN 2009]

Migration

Adult Spanish Imperial Eagles are sedentary birds and stay in their territory all year. Juvenile birds disperse after becoming
independent. Some birds breed close to their birth site when they are old enough, others settle farther away from their
birth site. This latter is called natal dispersal. In a study in Spain that involved tracking 84 nestlings between 1990 and 2002,
the mean natal dispersal distance was 101.2 km with a maximum of 310 km (255 km for females) [Gonzáles & Margalida 2008].

3) Return to the vicinity of the natal area (after being 16 month or older).

During the dispersal phase the eagles often leave protected areas and therefore are often exposed to many human related threats (see
below).

Breeding and Reproduction

Normally starts breeding with 4-5 years. Nests are normally built on trees, recently some pairs started using electricity pylons. Normally 1-4 eggs are laid.
The incubation period is about 44 days and the young stay in the nest for about 75 days.
After fledging the young stay within their natal area for another 116-162 days before dispersing. [HBW Alive 2014], [Mebs & Schmidt 2014].

Food and hunting

The most important prey is the rabbit. In a study in the Montes de Toledo (Castilla-La Manche, Spain) the pellets of
Spanish Imperial Eagles were studied. In 93%, remains of rabbits were found. Other important prey was carrion (found
in 20% of the pellets), pigeons (8.4%), other birds (10%), hare (2%), reptiles (1.8)
and partridge (0.6%) [Castaño López 2005]. That clearly shows how important the rabbit is
for the species.
In the Doñana National Park more waterfowl like Greylag Geese, Coots and Mallards are hunted, as well as
Magpies and Wood Pigeons [Mebs & Schmidt 2014].

Population

One of the rarest raptors in the world. In 1974 only about 50 pairs were counted [Castaño López 2005]. But since
then the population has increased and in 2008 253 territories were occupied, 4 in Portugal, the rest in
Spain. 310 young eagles fledged in 2008. [Gonzáles 2009].
In 2010, 282 pairs were observed, 279 in Spain and 3 in Portugal. This is 16 pairs more than in 2009. 341 young fledged, the highest number ever recorded [SEO 2011].

Threats

On of the most serious threats is electrocution. In 2008, 33 electrocuted Spanish Imperial Eagles were found
[Gonzáles 2009]. Despite work to make powerlines safe in many areas, there are still many eagles dying because
of electrocution. The expanding population and dispersing juveniles visit new areas where powerlines have not yet been
made safe.
Poisoning is another serious problem. Many eagles and vultures are poisoned in Spain every year. Often the poisoning
is targeted at the raptors themselves. In other cases the target species are mammals like foxes but eagles also eat
carrion and so die, too.
In a study that examined the death of 267 Spanish Imperial Eagles between 1989 and 2004, 91.7% of the causes of
mortality (where the cause of death could be determined) were of human origin. Electrocution and poisoning were
by far the most common causes of death. 115 Spanish Imperial Eagles were electrocuted and 74 were poisoned. Other
causes of death were shooting (16 cases) and disease (13 cases) [Gonzáles & Margalida 2008].

Conservation

Illegal poisoning must be stopped. Public education and better law enforcement are necessary. Powerlines should
all be made safe for birds. Not only in the breeding areas, but also in the dispersal areas where many juvenile and
immature birds can be found after they leave their natal area. In Spain, several organisations like WWF or
SEO/BirdLife Spain are working on conservation programs for the Spanish Imperial Eagle. The national and some regional
governments are also working to protect the species.
Valuable habitat must be protected. Roads or windfarms should not be build in valuable habitat, close to nests or
in dispersal areas.
The recent population increase is encouraging. If poisoning and electrocution can be reduced significantly, the population
should be able to increase a lot more.